Gelcells are supplied fully charged. I would expect a charger to switch to trickle charge after an hour or so when using it with a new battery for the first time. The price you quote for a charger seems pretty cheap, you need to check the voltage across the battery.

I usually charge them from a current limited home made power supply, set to 13.8 Volts. When the current drops to 200 - 400 mA from an original 2 Amps, it's time to turn off the charger.

My Harbor Freight charger has two LEDs. One that shows when it is charging, and one that shows when it is not. After the battery is charged, you'll see it cycle between these once in a while. It's been a while since I checked the voltages, but it seems that it charges until you get to about 14.4 volts. Then it switches off but lights the "charged" LED. When the voltage drops to around 13V (I think), it switches on again.

Harbor Freight also has a trickle-type charger that never shuts off. It only has one LED. Any chance you got this one?

G4AON is right, gel cells should be pretty close to 100% if they're new and haven't been sitting on a shelf for a couple years. I too suspect you have a battery 'maintainer', not a charger. These chargers don't supply enough current to charge a depleted battery (in any reasonable amount of time). Spend the bucks and get a real two or three stage charger built for gel cells (not motorcycle or automotive batteries). I use a PowerSonic 124000 charger for my gel cells. Some of my gels are over 6 years old and still near full capacity. Rechargeable batteries usually don't die, they're murdered, through improper charging or storage. Buy the right charger and you'll never have to worry about it.

It will do a good job of maintaining a battery once charged, but isn't very good for "charging" all but the smallest batteries. Either keep it as a "maintainer" for other batteries (it wasn't THAT expensive on sale, and you can probably find a use for it) or exchange it for a full-function charger.

His battery is only 5AH. Actually a 1.5A charger is a little big to bulk charge a 5AH SLA battery. SLAs normally have a maximum bulk charge rate around 0.15C which would be only 750mA for a 5AH battery.

Once the battery is charged, the charger should switch to a constant voltage of 13.8V. At that voltage the battery will draw only the current it needs to stay up with the self discharge rate.

I expect they are calling it a "trickle" charger because it was intended for use on a much larger battery. On a 70AH battery, 1.5A is a trickle charge.

I use a 3 stage charger for all of my beatteries that are not connected to solar.

you will see a 3rd wire usually yellow that also goes to the + post. these have a hi current ( mine is 1 amp) at a lower voltage(13.7 ??) , then the do a high voltage , low current topper (14,6 volts??) then drop to a maintainer charge ( 12.7 v at low current??)

I may be off on the voltages but it works like that. Mine id fro A & A engineering, about $50 for an assembled one.

You may want to check with the maker. Some of those are gel batteries, while others are now AGM batteries. The charging characteristics and everything else about the two are slightly different. To get the best life from it, you'd need to confirm which one it is. Both are "Sealed Lead Acid" aka SLA or SLA/VR (valve regulated) types, but they are not the same thing.

Due to charging losses, recharging any battery generally takes roughly 120% of the time that you'd expect based on "just" putting the capacity back in, i.e. you can expect about a 20% charging loss.

Mark, I don't know how you get full capacity of GEL cells after 6 years. Anything I've seen from the makers indicates that even on a float charge, they won't make it half that long without substantial losses, no matter how respectfully you treat them.

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